Technical Field of the Invention
The invention relates to a photovoltaic element comprising a resonator. The element has a high transformation efficiency rate related to the transformation of the energy of light to electric energy. The element comprises a semiconductor structure located between a pair of electrodes.
State of the Art
In contemporary photovoltaics, more than fifty-year-old principles of transforming solar electromagnetic radiation (wideband electromagnetic radiation within the wavelength range of 100 nm to 10000 nm) are generally applied. Solar cells are composed of two semiconductor layers (with silicon being the usual material) located between two metal electrodes. One of the layers (an N-type material) comprises a multitude of negatively charged electrons, whereas the other layer (a P-type material) shows a large number of “holes” definable as void spaces that easily accept electrons. Devices transforming electromagnetic waves to a lower-frequency electromagnetic wave, or a direct component, are known as transverters/converters. For this purpose, semiconductor structures with differing concepts and types of architecture are applied, respecting only experimental results of the electromagnetic wave transformation effect.
Antennas, detectors, or structures designed to date are not tuned into resonance; the applied semiconductor structures face considerable difficulty in dealing with emerging standing electromagnetic waves.
Similar solutions utilize the principles of antennas as well as the transformation of a progressive electromagnetic wave to another type of electromagnetic radiation (namely, a progressive electromagnetic wave having different polarization or a standing electromagnetic wave) and its subsequent processing. Certain problems occur in connection with the impinging electromagnetic wave and its reflection as well as in relation to the wide-spectrum character of solar radiation. In general, it is not easy to construct an antenna capable of maintaining the designed characteristics in the wide spectrum for the period of several decades.
U.S. Pat. No. 8,081,931, issued Dec. 6, 2011, to Novack et al, the disclosure of which is incorporated herein by reference, discloses methods, devices, and systems for harvesting energy from electromagnetic radiation, including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the grand plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of at least one of the resonance element's resonant frequency. At least one energy transfer element may be associated with at least one resonance element.
In a publication by P. Fiala et al. entitled “Tuned Structures for Special THz Applications”, in PIERS Proceedings, Beijing, CHINA, dated Mar. 23-27, 2009, particulars of new research in the special structures used for THz applications were presented. A practical application is focused on impedance matching of the basic THz structure for the wave transformation. An element produced by nanotechnology was numerically modelled and an analysis of obtained results was used for a subsequent chase of design. A final design was prepared for mid-infrared and long-infrared wavelength applications. According to the interpretation of the results, a basic design was prepared for experimental fabrication of a first prototype of nanostructure elements.
In another publication by Pavel Fiala et al. entitled “Tuned Periodical Structures—Model, Experiments in THz Band Applied in Safety Application”, in PIERS Proceedings, Cambridge, USA, dated Jul. 5-8, 2010, an insight into the issues of integration and application of non-lethal weapons and devices in the field of protection against special-type weapons is provided. Structures like materials, left-handed type models were analyzed and prepared to experimental measurements.
In a publication by D. K. Kotter et al. entitled “Theory and Manufacturing Processes of Solar Nanoantenna Electromagnetic Collectors”, in the Journal of Solar Energy Engineering, Vol. 132, No. 1, dated February 2010, research exploring a new and efficient approach for producing electricity from the abundant energy of the sun, using nanoantenna (nantenna) electro-magnetic collectors (NECs) is described. NEC devices target mid-infrared wavelengths, where conventional photovoltaic (PV) solar cells are inefficient and where there is an abundance of solar energy. The initial concept of designing NECs was based on the scaling of radio frequency antenna theory to infrared and visible regions. This approach initially proved unsuccessful because the optical behavior of materials in the terahertz (THz) region was overlooked and, in addition, economical nanofabrication methods were not previously available to produce optical antenna elements. This paper demonstrates progress in addressing significant technological barriers including: (1) development of frequency-dependent modeling of double-feedpoint square spiral nantenna elements, (2) selection of materials with proper THz properties, and (3) development of novel manufacturing methods that could potentially enable economical large-scale manufacturing. It has been shown that antennas can collect infrared energy and induce THz currents and cost-effective proof-of-concept fabrication techniques have been developed for the large-scale manufacture of simple square-loop nantenna arrays. Future work is planned to embed rectifiers into double-feedpoint antenna structures. This work represents an important first step toward the ultimate realization of a low-cost device that will collect as well as convert radiation into electricity. This could lead to a broadband, high conversion efficiency low-cost solution to complement conventional PV devices.
For the purpose of this application, following definitions are provided.
A semiconductor material is characterized in that its area includes moving electric charge carriers and also such carriers or conditions that restrict the extent or degree of motion and transfer of a free electric charge. These carriers or conditions are, from the electrical perspective, partially conductive in given frequency bands of applied electromagnetic wave; thus, they are semi conductive from the electrical perspective.
A dielectric is characterized in that its area includes moving charge carriers, whose number is nevertheless very low; these carriers move resulting electric charge in the area of the dielectric. The area also includes such electric charge carriers or conditions that markedly restrict or, in a limited case, wholly impede the extent or degree of motion and transfer of a free electric charge. These carriers or conditions are, from the electrical perspective, non-conductive in given frequency bands of an applied electromagnetic wave; thus, there are no free electric charge carriers (or, if otherwise, they are found only at rates below 1% of the total concentration).
A semiconductor layer can be fabricated, within chemical-technological material engineering, from materials that include, for example, inorganic, organic, macromolecular and micromolecular matter, polymers, nanoparticles, nanocomposites and nanomaterials in general, biological structures, and atomic or molecular chains or clusters and their variously combined wholes. These technologies are known as diffusion technologies of semiconductor elements of type P or N (as disclosed in a publication by H. S. Rauschenbach entitled “Solar Cell Array Design Handbook: The Principles and Technology of Photovoltaic Energy Conversion”, and in U.S. Pat. No. 2,530,110, issued to J. R. Woodyard, on Nov. 14, 1959, the disclosure of which is incorporated herein by references). Furthermore, relevant technologies for the manufacture of semiconductors and semiconductor inorganic structures are lift-off processes with photoresists, developers, remover, adhesion promoters, etchants and solvents (as disclosed by MicroChemicals GmbH, Germany). Lastly, technologies for the manufacture of organic micro and macromolecular elements forming the planar and the spatial part of a resonator are known from OLED technologies (as disclosed in a publication by Zakya H. Kafai et al. entitled “Organic Electroluminescence” by CRC Press (2005)). Specific examples of chain-like amorphous materials include 4,4′-di-(1,4-buta-1,3-diynyl)benzoic acid, 4,4′4″-tris(diphenylamino)triphenylamine, 1,3,5-tris(diphenylamino)benzene and 1,3,5-tris[4-(diphenylamino)phenyl]benzene, and combinations thereof (see also a publication by Jan Čechal et al. entitled “Convergent and Divergent Two-Dimensional Coordination Networks Formed through Substrate-Activated or Quenched Alkynyl Ligation”).
In a layer with minimum electromagnetic damping occurs a minimal decrease (of up to 10%) of the amplitude of the electromagnetic wave entering the specific volume of material.
In a layer with electromagnetic damping, the amplitude of a progressive electromagnetic wave decreases by at least 10%.
The planar (here denoted as “first”) part of a resonator is characterized by planar fabrication. In a technical embodiment, this is a fabricated resonator in which two dimensions markedly (at least tenfold) dominate over a third dimension.
The spatial (here denoted as “second”) part of a resonator is characterized by non-planar fabrication. In a technical embodiment, this is a fabricated resonator in which two dimensions do not markedly (at least tenfold) dominate over a third dimension.
A reference electrode is an electrode to which an electrode of an identical character is connected from an external area; in an internal area, the electrode assumes the function of a relating electric field, and relative electric potential is created; in a direct component of an electromagnetic wave, an electric potential will appear to which other electric potentials in a given structure are related.
A dopant material is such material which, in the exemplary embodiment with an inorganic semiconductor, causes a higher concentration of electric charge carriers.